Spring-cushion device.



WITN EBSES o.. WASHINGTON. u.

miran sTaTEs TAT oFFroE.

CLARENCE 1. BYRNES, OF SEWICKLEY, PENNSYLVANIA.

SPRING-CUSHION DEVICE.

To all Ywhom 'it may concern.'

Be it known that I, CLARENCE P.,BYnNEs, of Sewickley, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Spring-Cushion Device, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification, in which-M Figure 1 is a horizontal section of a tandem draft gear, constructed in accordance with my invention; and Fig. 2 is a sectional side elevation of the same.

My invention relates to the class of springs set forth in my Patent, Number 743,689, dated November 10, 1903.

The object of the invention is to increase the resistance of the spring and avoid liability of breaking, bending or uncoiling of the thinner end portion or portions of the spring, which are tapered down from the full cross section, or cut ofi' at full section. In the externally coiled springs, such as shown in the present drawings, it has been found that under extreme loads of between 200,000 and 300,000 pounds, the end portion of the spring at one end tends to be forced downwardly and outwardly out of its normal position, thus starting to uncoil or distort the true shape of the spring. This may happen whether the spring is provided with a ta ered end or cut oif at full cross section. Iy invention is designed to prevent this bending, breaking or unwinding of the partial cut coil and consists in holding this end coil in its proper position by a pocket follower.

In the drawings, in which I have shown the invention as applied to a tandem gear, 2 and 3 representl tandem gear springs. Of these springs, 2 shows approximately the section of my prior Patent, Number 743,689, while 3 shows a changed section, giving the same effect but with ak double-headed cross section, making the section uniform at both ends and reversible. This section also tends to stiifen the spring and increase its resistance during the stroke. With this spring,

vI preferably employ follower plates 4:, 5, 6

and 7, these plates having pockets, preferabl of annular form, to receive the partial endy coils of the springs. These annular pockets may be formed by recessing the folower or by the use of projecting lips, or providing the follower with any other device or mechanism which acta as retainer for Specification of Letters Patent.

Patented Nov. 30, 1915.

the end coil, to prevent its distortion. I have shown these followers as duplicates of each other, and this is the preferred form, since only one type needs tov be kept in Stock. The inner projections -8' ofV these followers, which fit within the end coils of the springs, are not essential, although I prefer to use them. In fact, the pocket or retaining device for the end coil is only necessary on that end of the spring having the partial coil which tends to be forced outwardly and downwardly from the next coil, as extreme pressure is applied; in the case of outside winding as here shown. The pocket may therefore have two retaining wallsinternal or external-or one retaining wall which is external at the end where the coil tends to force outwardly. The followers may have an external retaining wall or pocket at one end, and an internal pocket at the other end, but this would require two types of follower, and would be objectionable for that reason.

In the device, as shown, 9 is the usual strap and 10 10 the check plates having stops 11 for the followers. In order to make the springs of the proper diameter relative to the strap 9 and space between the draft sills, Ipreferably recess the followers at opposite sides, as shown at 12, to allow the strap to pass within these slots. The followers are thus enabled to coact in the usual manner with the stops, while at the same time, the spring may be made of the desirable diameter, according to M. C. B. practice.

13 represents the draft sills, and 14 the shank of the coupler, to which the strap is secured in the usual manner. In the form shown, a central block 15 is secured to the opposite sides of the stra 9, between the followers 5 and 6. This glves simultaneous movement to the same amount upon both springs, giving each spring the full stroke in the usual manner of the ordinary draft ri ging springs.

he advantages of my invention result from the greater resistance obtained and the doing away with the liability of unwinding, breakin or bending down the partial end coil o the spring. By employing a retainer for this partial end coil, the cam operation of one coil upon the next is prevented from distorting the partial end coil and starting it to unwind the spring.

Other forms of retainers for the partial end c'oil may be employed. The retaining device may be employed at one or both ends, and may be either internal or external or both.

I claim:

l. The combination with a helical spring haring its coils arranged to give cam action upon wich other around diil'erent parts of their circumference, and an end plate having a surrounding recess of a shape correspending to the normal cross section of the spring and arranged to prevent undue distcrlion of the mrtial end coil in any position thereof, sa stantially as described.

2. The combination wlth a helical spring haring its coils arranged to give cani action upon cach other around their circumference, of end plates having surrounding recesses correspondingr to the normal Cross section of the. spring, each of said recesses being arranged to prevent undue distortion of the partial end coils in any position of the same within the recesses, substantially as described.

In testimony whereof, I have hereunto Set ny hand.

CLARENCE l). BYRNES. Witnesses:

R. A. BALmlnsoN,

H. M. Conwix.

Copies of this patent may be obtained for tive cents each, by addressing the Commissioner of Patents. Washington. D. C." 

